Research On Slamming Load Prediction And Structural Strength Assessment Method Of Semi-submersible Platform

In recent years,the frequency of super typhoons is increasing.Wave slamming caused by extreme sea conditions is an important cause of various accidents,which has aroused the interest of researchers in solving such problems and gradually carried out in-depth researchIn this paper,based on CFD method,the numerical simulation of wave is carried out by using the EOM.Through the analysis of mesh convergence,the optimal mesh generation method is determined.On this basis,the wave slamming effects of plates and cylinders are studied and compared with the experimental results and empirical formulas.The results show that the simulation results are good,which shows that the method is more reliable to solve such problems.Then,the wave climbing and slamming effects of the semi-submersible platform in the fixed and moving state are studied,and a set of wave slamming simulation solution is proposed Based on this solution,the parameter sensitivity analysis of the wave slamming is carried out,including the wave steepness parameter,scattering parameter,incident angle,the joint action of wave and current.The results show that the junction of the back column and the lower deck needs to be paid more attention to,and the negative air gap and wave slamming are very easy to occur in this area,which has a great potential safety hazard;When the wave steepness parameter is large and the scattering parameter is small,the climbing effect of incident wave is more obvious and the slamming effect is more stronger;There are many factors influencing the climbing and slamming effects under the joint action of wave and current,which need to be determined according to different positions of columns,scattering parameters and wave steepness parametersConsidering the influence of the wave slamming load on the structural strength of the platform,combined with the DNV standard,the structural strength of the platform is analyzed and evaluated by the dynamic and static analysis methods.The results show that the strain of static analysis is about 1.2 times of that of dynamic analysis,and the calculation time is short,the resource is low,so it has a great advantage in engineering application.